title: Non-neoplastic bulky mediastinal mass presentation in an adolescent patient: a case report.
abstract: BACKGROUND
  Mediastinal masses in pediatric patients are very heterogeneous in origin and etiology. In the first decade of life, 70% of the mediastinal masses are benign whereas malignant tumors are more frequent in the second decade of life. Among the mediastinal masses, lymph nodes are the most common involved structures and could be enlarged due to a lymphoma, leukemia, metastatic disease, or due to infectious diseases as sarcoidosis, tuberculosis and others.
  
  
  METHODS
  We report a case of a 13-year-old Caucasian girl who came to the emergency room with a history of intermittent fever, weight loss and night sweating for at least 1 month. A radiologic image work-up presented an anterior and posterior mediastinal mass. The 18F-fluorodeoxyglucose positron emission tomography presented a high maximum standard uptake value, which directed our decision for mediastinal biopsy for diagnostic elucidation. Histologic examination described the mass as granulomatous tuberculosis. The patient was treated with anti-tuberculosis therapy and developed a full clinical recovery.
  
  
  CONCLUSIONS
  The present case report demonstrates that a bulky mediastinal lymphadenopathy detected on 18F-fluorodeoxyglucose positron emission tomography is not always a malignant lesion, and in countries where tuberculosis is endemic, this etiology should not be forgotten during clinical investigations. There is a need for more accurate cut-off values for this technology; meanwhile, the further investigation of patients with bulky mediastinal masses with procedures such as the open biopsy is indispensable.
authors.affiliation: Disciplina de Hematologia e Hemoterapia da Faculdade de Medicina da Universidade de Sao Paulo, Av, Dr, Eneas de Carvalho Aguiar 155, primeiro andar, sala 30, Sao Paulo, CEP 05403-000, Brazil. isbendit@usp.br.
authors.forename: Paula Fraiman
authors.initials: PF
authors.lastname: Blatyta
authors.forename: Claudio Carneiro
authors.initials: CC
authors.lastname: Borba
authors.forename: Ligia Reis
authors.initials: LR
authors.lastname: de Queiroz
authors.forename: Raphael Salles Scortegagna
authors.initials: RS
authors.lastname: de Medeiros
authors.forename: Fabiana Gomes
authors.initials: FG
authors.lastname: de Campos
authors.forename: Israel
authors.initials: I
authors.lastname: Bendit